Yea, setElementData should work, maybe somin like;
for k, v in ipairs (getElementsByType("elementNode")) do
setElementData(v,"x",nil)
setElementData(v,"y",nil)
setElementData(v,"z",nil)
end
That is, if the element data is "x", "y", and "z", and you're using a .map file (and of course you want to do it for every one of that element)l.